Thecus N8800+ or a two-unit storage for eight disks

Hardly had we published the review of one-unit storage Thecus 1U4200XXXR, when another rack-mount storage by the same vendor N8800+ got into our laboratory. It is a 2U storage that allows up to eight SATA II disks to be connected. As both NAS’s have similar characteristics, we are not going to study the N8800+ web-interface in detail, but dwell on the device hardware features, conduct the tests of data access speed. We are also planning to compare the results obtained with the results for 1U4200XXXR from the XXX line. So, first things first.

Thecus N8800+ is performed in a metal case with the dimension of 626*480*87 mm in length, width and height, respectively, and is intended for being mounted onto a 19” telecommunication rack with the help of the rails provided as a unit. Mounting brackets are attached to the front along the sides of the device, but mounting the storage to the rack only using these is not allowed. The front panel is closed by the punched metal door, which excludes accidental pressings N8800+ control buttons. Behind it there are eight HDD-baskets, an LCD-monitor, ON/OFF/Reload buttons, four control buttons (, , and Esc) for changing operation parameters of the storage in local access (not in the network) and also two USB 2.0 ports. It`s important to mention that in case of firm placement of the equipment at the cabinet, assembling the device on its own rails can be impossible. As well as opening the punched door may be complicated or totally impossible if some device with the front part jutting out is placed under the storage.

Two power modules, two USB 2.0 ports and two Gigabit Ethernet interfaces, one DB9 port for connecting with UPS and one eSATA-port are placed on the back panel of N8800+. You can also find two slots for installing an extra extension card. Unfortunately, as it can be seen further, there is only one PCI-E 8X slot. For example, a 10GE network card can be installed here.

The model R8P-400 by SURE STAR, a power supply company, is used as a power unit of the device. The power supplies themselves are installed in a single case which is connected to external power. Each block is equipped with 40*40*20 mm fans.

Thecus N8800+ electronic filling consists of thirteen boards altogether, twelve of which perform the functions of cable configurations and slot connectors. We present the photos of some of them to our readers.

The storage is divided into two equal parts inside. One of them contains hard disks. And the other one – power units and the motherboard. Along the partition four 80*80*25 mm fans of hot swapping are placed.

RAM is represented by a DSL DDR2-800 2Gbyte module. There are two slots for RAM on the motherboard altogether.

Despite the size of RAM being twice as big as one of the model examined before, the memory itself is DDR2 and the size of flash-memory is four times less and is of 128 Mbyte. As in 1U4200XXX flash-memory is doubled here and made by Afaya: MDM4LRSU128MBPCF and MDM4LSU128MBPCF. One of the modules is protected from recording and contains the back-up copy of firmware. Such board can only be used in case of a serious malfunction along with the firmware of the main bank. Samsung K9F1G08U08B microchips are used as flash-memory, and controlling functions are performed by SSS 8883 A5-S3CHMNFK-004F. Thecus has already used such controllers, for example in the model N4200.

The main elements of the motherboard itself are placed on one side, where you can find the following marking: N7700/8800 Ver:1.4. Besides two back USB 2.0 ports there are also two inward ports on the board. IntelLF80538 440 with the frequency of 1.86 GHz, cash of 1 Mbyte and FSB of 533 МHz performs the functions of the CPU. The south bridge is represented by an Intel NH82801GHM chip and the input-output controller – by Winbond W83627EHC. Also some module under the big radiator without a fan was found, but there was no marking on it so we were not able to identify it. Network connections are provided by two Intel WG82574L chips. Four SiliconImageSil3132CNU modules provide the connection of two SATA300 (SATAII) HDD’s to the PCI-E bus.

Thecus N8800+ allows two ways of firmware upgrade: manual and semiautomatic. In the manual mode the user himself has to download a file (approximately 63 Mbyte) with the image of the firmware from the vendor’s web-site and then address the item "Software Update" of the “Management” menu. For the semiautomatic mode you`ll first need to register your device with the help of the item “On-line Register” in the “System Information” menu.

After such registration in the same menu item you will be able to see the list of available updates.

However, having chosen the necessary update, the user is nevertheless forwarded to the vendor’s English-language web-site to download the chosen firmware version. We believe that the language choice on the web-site could depend on the chosen language of the web-interface of the device.

We have downloaded the firmware version 5.01.04 from the web-site and started the update process with the help of the point “Update” in the "Management" menu.

The whole upgrade procedure takes about three minutes, and then you need to reload the system (70 seconds).

Thecus N8800+ doesn't limit the user by the standard number of the storage potential and allows to setup some extension modules. Managing of the modules is performed by means of the items in the «Application server» web-interface group. The «Auto module installation» item provides the administrator with the opportunity to search for the available modules in vendor's on-line base or to upload the module downloaded in advance himself. As an example we decided to set up the module DLM2 making the uploading via protocols HTTP, FTP, BT and eMule feasible.

After installation of a module it will need launching with the help of the point “Modules”, then you can pass to its adjustment.

Now we are going to examine sample facilities of N8800+ web-interface.

The access to the storage web-interface is realized by the browser’s addressing to 192.168.1.100. Of course, the administrator's host must be from the 192.168.1.0/24 subnet. On entering the user will be requested a password that is admin by default.

After entering correct account data, the user gets to the device homepage available in thirteen languages. We won't describe all the options of each menu item in detail, but just turn to the most interesting ones.

The «System information» group items reflect the information about the storage model and the current firmware version, started services and device uptime, CPU loading and its cooling. Moreover there is some available information about all the events that N8800+ experienced. The transfer of the journal information to the remote Syslog-server is also possible.

Besides transferring the information to the Syslog-server it is also possible to send notifications via e-mails with the help of the «Notifications» item in the “System Management” group. The rest of this group items allow managing the time of the device, updating the firmware, configuring the schedule of the storage's turning-on and off, changing the administrator's password and managing the N8800+ configuration, rebooting and shutting down the device, checking the file system, enabling or disabling the Wake-on-LAN, configuring the SNMP parameters and managing the UI login functions.

The sub items of the “System Network” group allow the administrator to configure WAN/LAN1 and LAN2 network interfaces, to manage the server DHCP, to aggregate physical connections.

The items of the “Storage” group are intended for HDD- and RAID-management, ISO image mounting, folder management and stacking.

Thecus N8800+ supports Active Directory and local database of users and groups, batch user creation, disc quotas management. The facilities mentioned above can be found in the items of the “User and Group Authentication” section.

Managing of the network file services Samba/CIFS, AFP, NFS, FTP, TFTP, HTTP/Web Disk and the services UPnP and Bonjour is performed in the “Network Service” menu.

With the help of the «Applications Server» group it is possible to manage extension modules and the iTunes server.

The description of the «Backup» group functions will be given below in the section, devoted to the problems of stacking, aggregating and backup.

The group «External Device» contains only two items: «Printer» and «Managing UPS» allowing configuring the printer or uninterruptable power supply connected to N8800+.

Here we are through with the review of the device web-interface and move to the information about options of the access via SNMP protocol.

To switch on the SNMP protocol support you ought to use the «SNMP» item of the “System Management” group.

We used the Getif utility, version 2.3.1 for connection. All in all there were detected six interfaces.

Now let's go to the Mbrowser tab where there are gathered all available parameters located in the .iso.org.dod.internet.mgmt.mib-2 brunch. The system data are presented in the parameters of the .iso.org.dod.internet.mgmt.mib-2.system brunch.

The interfaces’ parameters are gathered in the .iso.org.dod.internet.mgmt.mib-2.interfaces brunch.

Statistical data about IP, ICMP, TCP, UDP and SNMP protocols are available in the corresponding items of the .iso.org.dod.internet.mgmt.mib-2 brunch.

Also several interesting parameters that are not related to the network are shown in the .iso.org.dod.internet.private as well.

We decided to get real data about the device's work via SNMP that is why we added N8800+ to the existing monitoring system on the basis of Cacti. The graph of the network interface load at the moment of writing one of this review's sections is given below.

Let's look into some more aspects of Thecus N8800+ work in the business environment.

Thecus enterprise NAS’s allow to be stacked to expand available disk space. Beside model N8800+ on hand, we have asked vendor for one more – N12000, with which we are going to stack. N12000 was chosen as the stack master because of its higher productivity, but no technical problems occur in case of using it as an ordinary stack member. The first thing when grouping the storages into a stack is creation of an iSCSI-target volume on the member device via “Space Allocation” item of “Storage” group, where you need to specify the resource name and its size. To prevent illegal connections CHAP-authentication may be used.

After creating iSCSI target volume on a member storage you have to connect it to the master device, for this purpose item “Stacking” of the “Storage” group is used, the administrator needs to specify IP-address of the connecting device and also detect the available resources.

A remote resource is not immediately available to the users after being connected, first it needs to be formatted, and afterwards you can get SMB, FTP and other protocols access to it.

Stacking under discussion is a connection of a remote block device according to iSCSI protocol using existing network infrastructure, which, on one hand, allows to remove limitations of the physical position of the devices relative to each other, but ,on the other hand, it loads network infrastructure severely as the data on its way from a member device to the user passes through the stack master. The problem mentioned above can be avoided if a detached physical interface is used for stacking, or by using 10GE NICs. It`s worth mentioning that a detached physical gigabit interface will be a bottleneck when grouping N12000 and N8800+ into a stack, as their speed values exceed the Gigabit Ethernet interface capacity greatly.

In case of the lack of bandwidth of one gigabit interface, aggregation of two physical ports can be conducted. In this case they play the role of one logical interface to access the storage. N8800+ allows to choose one of several variants (Load Balance, Failover, Balance-XOR, 802.3ad, Balance-TLB and Balance-ALB) of load distribution among the physical links.

We decided to allow the access to the storage to a group of local users connected to the switch Cisco Catalyst 2950 (WS-C2950G-24-EI), which has twenty four Fast Ethernet ports and two Gigabit Ethernet port. N8800+ was connected to two gigabit ports of the switch, which configuration is shown below. IEEE 802.3ad protocol was used for balancing.

It`s worth mentioning that Cisco Catalyst switch is exclusively L2-device and allows conducting balance inside the aggregated channel based only on MAC-addresses, which is unacceptable in case of moving the storage to a separate segment, as all the requests will pass to it from a unique MAC-address – MAC-address of the segment gateway. L3 switches balancing the data transmitted through the aggregated channel not only based on L2 headers, but also using L3 headers of OSI model (IP). Cisco Catalyst 3750 is an example of such switch.

Despite being an enterprise solution, N8800+ does not have built-in mechanisms allowing high-availability, as the model mentioned before – N12000, however, standard means HA and load balancing are limitedly applicable to it. For example, organization of a port-channel can also be defined as making redundancy, allowing to protect from failures of patch-cord, network interface of the storage or switch port. As a matter of fact, it is possible to retain safety in case of the switch's failure either in organizing the switch stack or while using the technologies like Cisco VSS which needs two switches Cisco Catalyst 6500 series with the supervisors Virtual Switching Supervisor 720-10GE for the realization. But the overview of Cisco VSS is beyond the scope of this review.

If the data available only in read-only mode are placed in the N8800+ storages, the exploitation of Cisco SLB (Server Load Balancing) executed on a separate device allows to spread the load between some storages and provide fault-tolerance. If the data of N8800+ are supposed to be used not only for reading but also for regular changing by users, to realize the system of some high availability there will emerge a need to engage Cisco EEM (Embedded Event Manager) or some other mechanisms of this kind. Let's describe such scheme via the example of using two storages of N8800+, one of which is working in active mode, the other is standby.

LAN2 interfaces are used only for linking the storages and their data synchronization. Such process can be launched every day at night or during the period of the lowest load on the storage system. Evidently, in case of the active device's failure all the data recorded on it after the latest synchronization will be lost. Synchronization can be accomplished with the help of Nsync/Rsync that are managed by the items «Nsync Target server», «Nsync», «Rsync Target server» and «Rsync» of the «Backup» group.

We would like to present the simplest logics of switching between the active and the standby storages. To initiate the switch it's essential for the interface Gi1/0/1 which is connected to the active storage, to be turned off. By using EEM it's possible to check the availability of the storage via ICMP, count the mistakes on the switch port and exploit a lot of other conditions of the EEM detector workflow. So, the active device is connected to the switch port Gi1/0/1, the standby is connected to Gi1/0/2. Both devices have the same IP-addresses (192.168.1.100/24) on the interfaces WAN/LAN1. Normally the interface Gi1/0/1 is switched on and Gi1/0/2 is switched off. We have written an applet that after the failure of the Gi1/0/1 interface administratively shuts it down and activates the Gi1/0/2 interface, after which it clears the ARP table of L3-switch and saves the configuration.

To see the registered applets is possible with the help of the command « sho ev man po reg». It's obvious that the described scheme won't save you from the malfunctioning of RAID-array on the active N8800+, but the failure of the whole storage will be successfully handled.

Thecus N8800+ has one more safety mechanism. It is Dual DOM allowing saving the configuration on the flash-memory doubling card in manual or auto modes. The corresponding configurations are performed via the «Dual DOM backup» item in the «Backup» group.

The first step to get acquainted with any sort of device is the boot process. As a rule of thumb we estimate the device booting time under which we mean the time interval between switching power on and receiving the first echo-reply via ICMP. Thecus N8800+ load takes 79 seconds which is a normal result for such kind of devices.

We either didn't come by the device's security that was checked with the help of Positive Technologies XSpider 7.7 (Demo build 3100) utility. We decided to check the storage security with the standard set of loaded services and modules, that is why all in all there were detected ten open ports: TCP-21 (FTP), TCP-80 (HTTP), UDP-137 (NetBIOS Name), TCP-139 (NetBIOS Samba), TCP-443 (HTTP SSL), TCP-445 (Microsoft DS), TCP-631 (HTTP), TCP-1194, TCP-2000 (FTP) and TCP-3260 (iscsi-target). The most interesting findings are given below. No serious security problems were detected.

At the moment of writing the testing section, we got an IP-camera ACTi TCM-5611 in our laboratory while Thecus N8800+ has a module allowing working with IP-cameras. Unfortunately we didn't manage to get the module IP_Cam version 3.0.0 to receive the data from the camera ACTi TCM-5611 with the firmware 4.09.22. Because of that we made the camera itself take pictures detecting any single move in its sight, and after that upload the photos on the FTP-server, working at N8800+. The detailed review of IP-camera ACTi TCM-5611 will be soon available on our site.

We made up our mind to test the package Twonkymedia that lets Thecus N8800+ fulfill the functions of the multimedia server. When the extension was installed and all the corresponding media files were downloaded to the module folder, we managed to connect to the storage with the help of Windows Media Player and look through all previously downloaded photos and movies and to listen to music.

Perhaps the most expected tests of N8800+ were the storage's performance tests, for which there was used a test stand with the following characteristics.

Components

PC

Laptop

Motherboard

ASUS P5K64 WS

ASUS M60J

CPU

Intel Core 2 Quad Q9500 2.83 GHz

Intel Core i7 of 720QM 1.6 GHz

RAM

DDR3 PC3-10700 OCZ 16 Gbytes

DDR3 PC3-10700 Kingston 8 Gbytes

NIC

Marvell Yukon 88E8001/8003/8010

Atheros AR8131

Operating system

Windows 7 x64 SP1 Rus

Windows 7 x64 SP1 Rus

The access test via NetBIOS was performed with the help of an Intel NASPT utility version 1.7.1. On the tested computers we deliberately reduced the available RAM to 2 Gbytes. Together with N8800+ we used the hard drives Seagate Constellation ES ST32000644NS with the volume of 2 Tbytes and the external USB-storage Transcend StoreJet 25M3 with the volume 750 Gbytes. The speed parameters of these storages are shown on the diagram below.

The first performance test of the storage was measuring the access speed via the NetBIOS protocol to the hard drive connected via USB.

Furthermore for each of the six types (JBOD, RAID0, RAID1, RAID5, RAID6 and RAID10) of supported RAID-arrays and four file systems (EXT3, EXT4, ZFS and XFS) the data access to the NetBIOS protocol was measured.

In some tests we came close to the channel Gigabit Ethernet limits, that is why those users who want to get higher speed, will have to set up optional network controllers 10GE or use the channel aggregation.

Moreover we decided to test the data access speed using the iSCSI protocol. The measure results are shown on the diagram below.

Thecus N8800+ supports encrypted disk arrays. Obviously we couldn't miss such an opportunity and carried out a comparing test of the access speed with the help of NetBIOS to the array RAID0 EXT3 with encryption and without it. Unfortunately we have to mention that access speeds to the encrypted array is significantly lower. The way-out in this case could be the use of the separated processor executing only encrypting operations or some support from the CPU of the extended command system AES.

This leads us to the end of the testing section. Let’s make conclusions.

In comparison with the previously tested rack-mountable network storage Thecus 1U4200XXXR, N8800+ has the twice bigger height (two units versus one), allows to set up just in a factor two more disks (eight instead of four), and demonstrated productivity on encrypted arrays exceeds the measures of 1U4200XXXR approximately in one and a half whereas data access speed placed on ordinary disk arrays (without encryption) are almost the same or insignificantly exceed the values shown by 1U4200XXXR. On the whole we are satisfied with the tested model, though we would like the Thecus designers to pay more attention to the problems of network equipment of the enterprise level mounting into the loaded telecommunication cabinets.

The advantages of Thecus N8800+ are given below.

High access speed to the storage.

Ability of network interfaces aggregation and stacking several storages.

Support of the optional 10GE NICs.

Redundant power supply.

Ability of controlling the device by using the buttons and the screen on the front panel.

Security against network attacks.

Possibility of free set up of the optional extension modules.

The weak points of Thecus N8800+ are the following.

The language of the opening page to load the new firmware doesn't depend on the chosen language in the storage web-interface.

Inconvenient mounting scheme of the device into the rack.

Absence of Cyrillic domains support.

Low access speed to the encrypted array.

Poor configuration of the metal door of the storage front panel.

At the moment of making up the review the average price of Thecus N8800+ without disks in Moscow online shops was 67000 rubles.

The author and the editorial team would like to thank the Tayle Company for the equipment provided for testing.